pub mod front_of_house {
    pub mod hosting {
        pub fn add_to_waitlist() {
            println!("add to wait list")
        }

        pub fn seat_at_table() {
            println!("seat at table");
        }
    }

   pub mod serving {
        pub fn take_order() {
            println!("tkorder");
        }

        pub fn serve_order() {
            println!("serve order");
        }

        pub fn take_payment() {
            println!("take payment");
        }
    }
}
